Certain solenoid-operated valves, such as fuel injectors, are typically assembled using traditional devices, such as threaded fasteners, crimps, and stakes. These joining techniques are subject to relaxation, spring-back, and lash which, over the useful life of a valve, may give rise to degradation in the valve's performance.
Accordingly, it is an object of the present invention to provide an improvement that avoids such degradation. Generally speaking, the present invention comprises the inclusion of a solenoid pre-loader that is arranged to keep the stator's solenoid disposed against an internal shoulder on the valve body. In the preferred embodiment of the invention, this shoulder is an annular lift spacer that sits on an integral internal shoulder of the valve body and has a thickness that calibrates the valve lift to a predetermined specification. Various forms of pre-loaders are contemplated and will be hereinafter described.
Drawings accompany the disclosure and depict a presently preferred embodiment of the invention according to the best mode contemplated at this time for carrying out the invention.